A spacewalking astronaut is stranded a few meters from the space-station door. His jet pack is broken, but he can take it off and toss it in order to propel himself toward the door. In what direction should he toss it?
A. toward the door
B. away from the door
C. toward the Earth
D. The answer cannot be determined from the information provided.

A truck with a mass of $2,000$ kg and moving at $15 \mathrm{~m} / \mathrm{s}$ collides with a stationary passenger car of mass $1,000 \mathrm{~kg}$. The two cars stick together after impact. Assuming that they are free to move afterward, what will the momentum of the truck+car object be?
A. $2,000 \mathrm{~kg} \mathrm{~m} / \mathrm{s}$
B. $3,000 \mathrm{~kg} \mathrm{~m} / \mathrm{s}$
C. $15,000 \mathrm{~kg} \mathrm{~m} / \mathrm{s}$
D. $30,000 \mathrm{~kg} \mathrm{~m} / \mathrm{s}$

A $1,500\mathrm{~kg}$ car sliding on frictionless ice at $15 \mathrm{~m} / \mathrm{s}$ hits a stationary, $2,500 \mathrm{~kg}$ minivan. The two vehicles are locked together after impact on the ice. What is their speed after impact?
A. $0 \mathrm{~m} / \mathrm{s}$
B. $5.6 \mathrm{~m} / \mathrm{s}$
C. $7.5 \mathrm{~m} / \mathrm{s}$
D. $15 \mathrm{~m} / \mathrm{s}$

Jimi $(80 \mathrm{~kg})$ and Tony ( $100 \mathrm{~kg})$ stand motionless on ice skates, facing each other at arm's length on a smooth, frozen pond. Which of the following actions will give Tony the greatest speed?
A. Tony pushes Jimi with $100 \mathrm{~N}$ of force for $0.1 \mathrm{~s}$.
B. Jimi pushes Tony with a force of $60 \mathrm{~N}$ for $0.2 \mathrm{~s}$.
C. Tony pushes Jimi with $200 \mathrm{~N}$ of force for $0.08 \mathrm{~s}$.
D. Jimi pushes Tony with a force of $250 \mathrm{~N}$ for $0.045$.

American Energy Review reported that $27 \%$ of American households burn wood. If a random sample of 500 American households is chosen, find the mean, variance, and standard deviation of the number of households that burn wood.

What was the role of physical geography in Napoleon's first significant defeat?

Assume all variables are binomial. (Note: If values are not found in Previous Table . use the binomial formula.)
High Blood Pressure Twenty percent of Americans ages $25$ to $74$ have high blood pressure. If $16$ randomly selected Americans ages $25$ to $74$ are selected, find each probability.
None will have high blood pressure.

Customers in a Bank A bank has a drive-through service. The number of customers arriving during a $15$-minute period is distributed as shown. Find the mean. variance, and standard deviation for the distribution.

$$\begin{array}{l|ccccc} \textbf{Number of customers} X & 0 & 1 & 2 & 3 & 4 \\ \hline \textbf{Probability} P(X) & 0.12 & 0.20 & 0.31 & 0.25 & 0.12 \end{array}$$

Two clouds collide and form another, more massive cloud. One cloud is stationary, while the other is traveling at $1 \mathrm{~m} / \mathrm{s}$. After the collision, the new, combined cloud travels with a velocity of $0.25 \mathrm{~m} / \mathrm{s}$. What is the ratio of the masses of the two original clouds?

In an elastic collision involving two balls where one is stationary before the collision, can you make any generalizations about the speed and direction of the two balls after the collision? Consider the situations where (a) the moving ball is more massive than the stationary one; (b) the stationary ball is more massive than the moving ball, and (c) the two balls have equal masses.

If In an elastic collision, a $1.0 \mathrm{~kg}$ ball moving at $1.0 \mathrm{~m} / \mathrm{s}$ collides with a $2.0 \mathrm{~kg}$ ball moving at $-2.0 \mathrm{~m} / \mathrm{s}$. The $2.0 \mathrm{~kg}$ ball transfers all of its momenta to the $1.0 \mathrm{~kg}$ ball.
a. What velocity does the $1.0 \mathrm{~kg}$ ball have after the collision?
b. What is the initial kinetic energy of the system?
c. What is the final kinetic energy of the system?

A stationary $165 \mathrm{~kg}$ football player is tackled by a $178 \mathrm{~kg}$ player running at $8 \mathrm{~m} / \mathrm{s}$
a. How fast are they moving after the collision?
b. What is the impulse imparted on the stationary player?
c. What is the impulse imparted on the moving player?

A $2,000 \mathrm{~kg}$ car moving at $10 \mathrm{~m} / \mathrm{s}$ collides head-on with a $2,500 \mathrm{~kg}$ car moving in the opposite direction at $15 \mathrm{~m} / \mathrm{s}$. The two cars are locked together after impact.
a. Is this an elastic or an inelastic collision? Why?
b. What is the speed of the cars after impact?
c. Calculate the kinetic energies of the cars, both before and after impact.
d. What fraction of the kinetic energy was lost during the impact? Where did the energy go?

If A $2.0 \mathrm{~kg}$ puck is moving east at $5.5 \mathrm{~m} / \mathrm{s}$. It catches up to and collides with a second identical puck moving due east at $3.0 \mathrm{~m} / \mathrm{s}$. The collision is perfectly inelastic.

a. What is the resulting velocity of the pucks?
b. What is the initial kinetic energy $E_{k i}$ of the system?
c. What is the change in kinetic energy, $\Delta E_k$, of the system as a result of the collision?
d. If the mass $m$ is doubled, but the initial velocities are unchanged, does the resulting velocity increase, decrease, or remain unchanged?